Medium feeding device and image reading apparatus

ABSTRACT

A medium feeding device includes a medium placing portion, a feeding roller that feeds paper, a medium movement detecting portion that is positioned on a placing region of the paper of the medium placing portion in a medium feeding direction and is capable of detecting movement of the paper being fed in a width direction intersecting the medium feeding direction, and a controller that stops feeding of the paper in a case in which a physical quantity relating to movement of paper in the width direction exceeds a predetermined threshold based on a detected result by the medium movement detecting portion.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 16/146,889, filed Sep. 28, 2018, which claims the benefit ofand priority to Japanese Patent Application No. 2017-191025, filed Sep.29, 2017, the disclosures of which are incorporated herein by referencein their entireties.

BACKGROUND 1. Technical Field

The present invention relates to a medium feeding device which feeds anoriginal document and an image reading apparatus which reads theoriginal document being fed by the medium feeding device.

2. Related Art

In a scanner which is an example of an image reading apparatus, a mediumfeeding device (also referred to as automatic document feeder (ADF)which automatically feeds an original document as a medium is provided,and the scanner may be configured to automatically feed and read aplurality of original documents.

Also, the medium feeding device may include an original document tray inwhich the plurality of original documents is placed on a placing surfaceand a feeding roller which feeds the original documents by coming intocontact with the original document set on the original document tray andbeing rotated.

In such a medium feeding device, a jam detecting portion which detects apaper jam (clogging) being generated at the time of feeding the originaldocuments by the feeding roller may be provided (for example,JP-A-2006-193286).

The jam detecting portion provided in the medium feeding devicedisclosed in JP-A-2006-193286 includes a transportation amount measuringportion which measures a transportation amount of a medium being fed bythe feeding roller and a medium detecting portion which is provided on adownstream side of the transportation amount measuring portion, and isconfigured to detect a paper jam in a case in which the medium detectingportion does not detect the medium even when the amount measured by thetransportation amount measuring portion exceeds a predetermined amount.The transportation amount measuring portion measures rotation amounts ofthe other rollers which are rotated in the same direction as the feedingroller or the feeding roller.

However, an original document bundle in which a plurality of originaldocuments is bound by a stapler may be erroneously placed on theoriginal document tray of the medium feeding device.

For example, in a case in which one corner of the original documentbundle is bound, there is a concern that a binding portion is pulledwhen a first sheet of the original document bundle is fed so that notonly the first sheet of the original document but also subsequent sheetsto a second sheet thereof may be damaged. Therefore, it is necessary toearly detect feeding of stapled original documents.

However, in a case in which a paper jam generated in the stapledoriginal document bundle is detected by the jam detecting portiondisclosed in JP-A-2006-193286, the feeding roller is needed to be drivenat least until the original documents reach the medium detecting portion(provided on downstream side of feeding roller), and thus there is aconcern that a damage to be generated in the original document mayincrease.

SUMMARY

An advantage of some aspects of the invention is to early detect atransportation failure of an original document in a medium feedingdevice or an image reading apparatus including the medium feedingdevice.

According to an aspect of the invention, there is provided a mediumfeeding device including a medium placing portion on which a medium isplaced, a feeding roller that feeds the medium placed on the mediumplacing portion by coming into contact with a surface of the mediumfacing the medium placing portion and being rotated, a medium movementdetecting portion that is positioned in a placing region of the mediumon the medium placing portion on an upstream side of the feeding rollerin a medium feeding direction and is capable of detecting movement ofthe medium being fed by the feeding roller in a width directionintersecting the medium feeding direction, and a controller that stopsfeeding of the medium in a case in which a physical quantity relating tothe movement of the medium in the width direction exceeds apredetermined threshold based on a detected result by the mediummovement detecting portion.

In this specification, the “job” in the medium feeding device means awork relating to an operation of feeding the medium in the mediumfeeding device, and the medium is stopped to be fed when the job isstopped.

In the configuration, since the controller stops the job in a case inwhich the physical quantity relating to the movement of the medium inthe width direction exceeds a predetermined threshold based on thedetected information by the medium movement detecting portion positionedon the upstream side of the feeding roller in the medium feedingdirection, it is possible to early detect the movement of the medium inthe width direction lead to a transportation failure of the medium andto suppress a damage to be generated in the medium. Also, as “thephysical quantity relating to the movement”, for example, a movementdistance, a moving speed, an acceleration rate, and the like areexemplified.

In the medium feeding device, a pair of the medium movement detectingportions may be provided with a gap therebetween in the width direction,the pair of medium movement detecting portions may be respectively setas a first medium movement detecting portion and a second mediummovement detecting portion, and the controller may stop the feeding ofthe medium in a case in which a difference between a physical quantityrelating to movement of the medium in the width direction being detectedby the first medium movement detecting portion and a physical quantityrelating to movement of the medium in the width direction being detectedby the second medium movement detecting portion exceeds a predeterminedthreshold.

In the configuration, since the pair of the medium movement detectingportions is provided with a gap therebetween in the width direction, andthe controller stops the job in a case in which the difference betweenthe physical quantity relating to the movement of the medium in thewidth direction being detected by the first medium movement detectingportion and the physical quantity relating to the movement of the mediumin the width direction being detected by the second medium movementdetecting portion exceeds a predetermined threshold, it is possible todetect a transportation failure of the medium, particularly, rotation ofthe medium, and to more reliably suppress a damage to be generated inthe medium.

According to another aspect of the invention, there is provided a mediumfeeding device including a medium placing portion on which a medium isplaced, a feeding roller that feeds the medium placed on the mediumplacing portion by coming into contact with a surface of the mediumfacing the medium placing portion and being rotated, a medium movementdetecting portion that is positioned in a placing region of the mediumon the medium placing portion on an upstream side of the feeding rollerin a medium feeding direction and is capable of detecting movement ofthe medium being fed by the feeding roller in the medium feedingdirection, and a controller that stops feeding of the medium in a casein which a stop section is shorter than a predetermined first thresholdwhen a moving section, the stop section, and a moving section of themedium in the medium feeding direction are detected by the mediummovement detecting portion in this order by receiving a detected resultby the medium movement detecting portion.

The “stop section” of the medium in the medium feeding direction is asection where the movement of the paper is not detected by the mediummovement detecting portion, and in addition to a case in which themedium movement detecting portion detects paper in a stop state of notbeing moved, a case in which the movement of the paper is not detectedbecause there is no paper is also included in the stop section.

In the configuration, based on the detected information by the mediummovement detecting portion positioned on the upstream side of thefeeding roller in the medium feeding direction, in a case in which thestop section is shorter than a predetermined threshold when the mediummovement detecting portion detects the moving section, the stop section,and the moving section of the medium in the medium feeding direction inthis order, that is, the controller early detects a feeding state (forexample, a state in which a subsequent medium along with a fed previousmedium is unintendedly fed due to a binding portion of a stapled mediumbundle) which is not detected in a normal state and stops the job, andthus it is possible to suppress a damage to be generated in the mediumat the time of generating a transportation failure.

Also, in this specification, the “section” of the moving section and thestop section means a time or a gap sectioned by a distance (length).

In the medium feeding device, the controller may be capable of referringto the second threshold that is shorter than the first threshold, andmay continue feeding of the medium in a case in which the stop sectionis equal to or less than the second threshold.

In a case in which a hole formed by a punching or the like is present inthe medium being fed, since a subsequent medium (referred to assubsequent medium) on a medium being fed (referred to as previousmedium) is detected by the medium movement detecting portion in a partcorresponding to the hole, apparently, the medium movement detectingportion detects stop of the medium. Also, when the part corresponding tothe hole passes through, the medium movement detecting portion detectsthe movement of the previous medium again.

Generally, since the hole formed by punching or the like is small, asection where the medium movement detecting portion detects the stopstate of the medium in the part corresponding to the hole is asignificantly short section, and the section is shorter than the firstthreshold for detecting the feeding (transportation failure) of thestapled medium bundle described above. Therefore, when the controllerperforms controlling with reference to only the first threshold, evennormal feeding of the medium having the hole is set to a transportationfailure, and thus a job is stopped.

In the configuration, since the controller is capable of referring thesecond threshold shorter than the first threshold, and continues the jobin a case in which the stop section is equal to or smaller than thesecond threshold, it is possible to suppress a false detection in whichfeeding of the medium having a small hole such as a punch hole isdetermined as a feeding abnormality.

In the medium feeding device, the medium movement detecting portion maybe configured to be capable of detecting both movement of the medium inthe medium feeding direction and movement in a width directionintersecting the medium feeding direction, and the controller may stopfeeding of the medium in a case in which a physical quantity relating tothe movement of the medium in the width direction exceeds apredetermined third threshold based on the detected result by the mediummovement detecting portion.

In the configuration, since the controller receives the detectedinformation by the medium movement detecting portion and stops a job ina case in which the physical quantity relating to the movement of themedium in the width direction exceeds the predetermined third threshold,in addition to an action effect described above, it is possible to earlydetect the movement of the medium in the width direction lead to atransportation failure of the medium and to more reliably suppress adamage to be generated in the medium.

In the medium feeding device, the feeding roller may be provided in acenter region of the medium in the width direction intersecting themedium feeding direction, and one medium movement detecting portion maybe provided in the center region in the width direction.

In the configuration, any one of the configurations described above isrealized in a so-called medium feeding device in a center paper feedingmanner in which the feeding roller is provided in the center region ofthe medium in the width direction intersecting the medium feedingdirection by providing one medium movement detecting portion in thecenter region in the width direction.

In the medium feeding device, a pair of the medium movement detectingportions may be provided with a gap therebetween in the width directionintersecting the medium feeding direction, the pair of the mediummovement detecting portions may be respectively set as a first mediummovement detecting portion and a second medium movement detectingportion, and the controller may stop a job in a case in which adifference between the stop section being detected by the first mediummovement detecting portion and the stop section being detected by thesecond medium movement detecting portion exceeds a predeterminedthreshold.

In the configuration, in a so-called medium feeding device in a centerpaper feeding manner in which the feeding roller is provided in thecenter region of the medium in the width direction intersecting themedium feeding direction, the pair of the medium movement detectingportions is provided with a gap therebetween so as to be positioned onboth sides of the feeding roller, and the controller stops the job in acase in which the difference between the stop section being detected bythe first medium movement detecting portion and the stop section beingdetected by the second medium movement detecting portion exceeds apredetermined threshold, and thus it is possible to more reliablysuppress a transportation failure.

According to still another aspect of the invention, there is provided amedium feeding device including a medium placing portion on which amedium is placed, a feeding roller that feeds the medium placed on themedium placing portion by coming into contact with a surface of themedium facing the medium placing portion and being rotated, a firstmedium movement detecting portion and a second medium movement detectingportion, as a medium movement detecting portion, that are positioned ina placing region of the medium on the medium placing portion on anupstream side of the feeding roller in the medium feeding direction, areprovided with a gap therebetween in a width direction intersecting themedium feeding direction as a pair, and are capable of detectingmovement of the medium being fed by the feeding roller in the mediumfeeding direction, and a controller that stops feeding of the medium ina case in which a difference between a physical quantity relating tomovement of the medium in the medium feeding direction being detected bythe first medium movement detecting portion and a physical quantityrelating to movement of the medium in the medium feeding direction beingdetected by the second medium movement detecting portion exceeds apredetermined threshold.

In the configuration, the first medium movement detecting portion andthe second medium movement detecting portion as the medium movementdetecting portion, which are capable of detecting the movement of themedium in the medium feeding direction, are provided as a pair with agap therebetween in the width direction, the controller stops the job ina case in which the difference between the physical quantity relating tothe movement of the medium in the medium feeding direction detected bythe first medium movement detecting portion and the physical quantityrelating to the movement of the medium in the medium feeding directiondetected by the second medium movement detecting portion exceeds apredetermined threshold, and thus it is possible to detect atransportation failure of the medium, particularly, rotation of themedium, and to more reliably suppress a damage to be generated in themedium.

According to still yet another aspect of the invention, there isprovided an image reading apparatus including a reading unit that readsa medium, and the medium feeding device according to any one of theconfigurations described above that feeds the medium toward the readingunit.

In the configuration, the same effects as that of the configurationsdescribed above are obtained in the image reading apparatus includingthe reading unit that reads the medium and the medium feeding devicethat feeds the medium toward the reading unit.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the accompanyingdrawings, wherein like numbers reference like elements.

FIG. 1 is an exterior perspective view illustrating a scanner accordingto the invention.

FIG. 2 is a perspective view illustrating the scanner according to theinvention when seen at a different angle from FIG. 1.

FIG. 3 is a side sectional view illustrating a paper transporting pathin the scanner according to the invention.

FIG. 4 is a perspective view illustrating a state in which an upperportion is removed from a lower portion.

FIG. 5 is a diagram describing normal feeding of paper.

FIG. 6 is a schematic plan view illustrating a normal feeding state ofthe paper.

FIG. 7 is a schematic plan view illustrating a state in which stapledpaper is placed on a medium placing portion with a clipped part thereofon a downstream side.

FIG. 8 is a schematic plan view illustrating an aspect in which thestapled paper is fed.

FIG. 9 is a diagram describing feeding of the stapled paper.

FIG. 10 is a schematic plan view illustrating a state in which thestapled paper is placed on the medium placing portion with the clippedpart thereof on an upstream side.

FIG. 11 is a schematic side view illustrating a state in which a statein which the stapled paper is placed on the medium placing portion withthe clipped part thereof on the upstream.

FIG. 12 is a schematic side view illustrating an aspect in which thestapled paper is fed.

FIG. 13 is a schematic side view illustrating the aspect in which thestapled paper is fed.

FIG. 14 is a schematic side view illustrating the aspect in which thestapled paper is fed.

FIG. 15 is a diagram describing the feeding of the stapled paper.

FIG. 16 is a schematic plan view of FIG. 13.

FIG. 17 is a schematic plan view of FIG. 14.

FIG. 18 is a schematic side view illustrating a state in which the paperhaving a punch hole is placed on the medium placing portion.

FIG. 19 is a diagram describing the feeding of the paper having thepunch hole.

FIG. 20 is a view describing the feeding of the paper in a mediumfeeding device of a second embodiment.

FIG. 21 is a view describing another example of the paper feeding in themedium feeding device of the second embodiment.

DESCRIPTION OF EXEMPLARY EMBODIMENTS First Embodiment

First, an outline of an image reading apparatus according to anembodiment of the invention will be described.

As an example of the image reading apparatus according to theembodiment, a document scanner (hereinafter, simply referred to asscanner 1) capable of reading at least one surface of a front surfaceand a rear surface of paper as a “medium” is exemplified.

FIG. 1 is an exterior perspective view illustrating a scanner accordingto the invention. FIG. 2 is a perspective view illustrating the scanneraccording to the invention seen at a different angle from FIG. 1. FIG. 3is a side sectional view illustrating a paper transporting path in thescanner according to the invention. FIG. 4 is a perspective viewillustrating a state in which an upper portion is removed from the lowerportion. FIG. 5 is a diagram describing normal feeding of paper. FIG. 6is a schematic plan view illustrating a normal feeding state of paper.FIG. 7 is a schematic plan view illustrating a state in which stapledpaper is placed on a medium placing portion with a clipped part thereofon a downstream side. FIG. 8 is a schematic plan view illustrating anaspect in which the stapled paper is fed. FIG. 9 is a diagram describingfeeding of the stapled paper.

FIG. 10 is a schematic plan view illustrating a state in which thestapled paper is placed on the medium placing portion with the clippedpart thereof on an upstream side. FIG. 11 is a schematic side viewillustrating a state in which a state in which the stapled paper isplaced on the medium placing portion with the clipped part thereof onthe upstream. FIG. 12 is a schematic side view illustrating an aspect inwhich the stapled paper is fed. FIG. 13 is a schematic side viewillustrating the aspect in which the stapled paper is fed. FIG. 14 is aschematic side view illustrating the aspect in which the stapled paperis fed. FIG. 15 is a diagram describing the feeding of the stapledpaper. FIG. 16 is a schematic plan view of FIG. 13. FIG. 17 is aschematic plan view of FIG. 14. FIG. 18 is a schematic side viewillustrating a state in which the paper having a punch hole is placed onthe medium placing portion. FIG. 19 is a diagram describing the feedingof the paper having the punch hole.

Regarding an X-Y-Z coordinate system illustrated in each drawing, an Xdirection indicates a paper width direction which is a width directionof the apparatus, and a Y direction indicates a paper transportingdirection. A Z direction indicates a direction intersecting the Ydirection and substantially orthogonal to a surface of paper which isgenerally transported. In addition, a +Y direction side is set to afront surface side of the apparatus, and a −Y direction side is set to arear surface side of the apparatus. In addition, a left side seen fromthe front surface side of the apparatus is set to a +X direction, and aright side is set to a −X direction. In addition, a +Z direction is setto an upper side (including upper portion, upper surface, and the like)of the apparatus, and a −Z direction side is set to a lower side(including lower portion, lower surface, and the like) of the apparatus.In addition, a direction (+Y direction side) where paper P is fed is setto a “downstream”, and an opposite direction thereof (−Y direction side)is set to an “upstream”.

Outline of Scanner

Hereinafter, a scanner 1 according to the invention will be describedmainly with reference to FIGS. 1 and 2.

The scanner 1 illustrated in FIGS. 1 and 2 includes an apparatus mainbody 2 in which a reading unit 20 (FIG. 3) reading an image of paper P(medium) is included.

The apparatus main body 2 is configured with a lower portion 3 and anupper portion 4. The upper portion 4 is attached to be openable andclosable with respect to a downstream side of the lower portion 3 in apaper transporting direction as a rotation fulcrum, the upper portion 4opens by being rotated to the front surface side of the apparatus, and apaper jam process of the paper P is easily performed by exposing a paperdocument transporting path of the paper P.

A medium feeding device 10 which feeds the paper P toward the readingunit 20 is provided in the apparatus main body 2.

A medium placing portion 11 on which the paper P is placed is providedon a rear surface side (−Y axis direction side) of the apparatus of theapparatus main body 2. The medium placing portion 11 is a configurationcomponent constituting the medium feeding device 10 and is provided tobe detachable from the apparatus main body 2. A reference number 11 a isa placing surface 11 a of the paper P. Also, a detail configuration ofthe medium feeding device 10 will be described later.

In addition, a pair of right and left edge guides 12 and 12 including aguide surface 13 which guides a side edge of the paper P in a widthdirection (X axis direction) intersecting a feeding direction (Y axisdirection) of the paper is provided on the medium placing portion 11.

The edge guides 12 and 12 are provided to be slidably movable in the Xaxis direction in accordance with a size of the paper P. In theembodiment, the edge guides 12 and 12 are configured to follow an Xmovement of one edge guide 12 (for example, +X side) by a knownrack-pinion mechanism and to move in a direction opposite to the otheredge guide 12 (−X side).

That is, in the medium placing portion 11, it is configured that thepaper P is provided at the center in the width direction, a feedingroller 14 to be described later is provided at a center region in thewidth direction, and thus the paper is fed in a so-called center paperfeeding method. FIG. 1 illustrates a state in which the edge guides 12and 12 are positioned on the outermost side, and FIG. 2 illustrates astate in which the edge guides 12 and 12 are positioned on the innermostside.

The medium placing portion 11 includes a first auxiliary paper support 8and a second auxiliary paper support 9. The first auxiliary papersupport 8 and the second auxiliary paper support 9 can be accommodatedin the medium placing portion 11 as illustrated in FIG. 2, and can bepulled out from the medium placing portion 11 as illustrated in FIG. 1,such that a length of the placing surface 11 a can be adjusted.

The apparatus main body 2 includes an operation panel 7 for displayingvarious operations of setting reading or performing reading, contents ofreading setting, and the like, on a front surface side of the apparatusof the upper portion 4.

A feeding port 6 connected to an inside of the apparatus main body 2 isprovided on the upper portion 4, and the paper P placed on the mediumplacing portion 11 is fed toward the reading unit 20 provided inside theapparatus main body 2 from the feeding port 6.

In addition, a paper discharging tray 5 to be described later isprovided on a front surface side of the apparatus of the lower portion3.

Regarding Paper Transporting Path in Scanner

Next, a paper transporting path in the scanner 1 will be describedmainly with reference to FIG. 3. Also, a dotted line in FIG. 3 indicatesa transporting path of the paper P.

In the scanner 1, the paper P which is an original document is fedtoward the reading unit 20 by the medium feeding device 10.

In the embodiment, the medium feeding device 10 as illustrated in FIG. 3includes the medium placing portion 11 described above, the feedingroller 14 feeding the paper P placed on the medium placing portion 11toward the reading unit 20, a medium movement detecting portion 21 (alsorefer to FIG. 1) positioned inside a placing region of the paper by themedium placing portion 11 on an upstream side of the feeding roller 14in a medium feeding direction (+Y direction), and a controller 19 whichcontrols operations of the medium feeding device 10. In addition, a pairof transporting rollers 16 is provided on the downstream side of thefeeding roller 14.

The invention includes a characteristic of a control of the operationsof the medium feeding device 10 by the controller 19 based on detectedinformation by the medium movement detecting portion 21.

The medium movement detecting portion 21 and the control by thecontroller 19 based on the detected information by the medium movementdetecting portion 21 will be described in detail after the papertransporting path is described.

In the medium feeding device 10, a separating roller 15, which nips thepaper P between the feeding roller 14 and the separating roller andseparates the paper, is provided at a position facing the feeding roller14 provided on a downstream side of the medium placing portion 11.

As illustrated in FIG. 4, the feeding roller 14 and the separatingroller 15 are provided in a center region in a medium width direction (Xaxis direction) intersecting a medium transporting direction (+Ydirection).

Return to FIG. 3, the paper P placed on the medium placing portion 11 isnipped by the feeding roller 14 which is rotatably provided with respectto the lower portion 3 and is fed toward a downstream side (+Y directionside). Specifically, when the feeding roller 14 comes into contact witha surface of the paper P facing the medium placing portion 11 and isrotated, the paper P is fed toward the downstream side. Therefore, in acase in which a plurality of sheets of paper P is set in the mediumplacing portion 11 in the scanner 1, the plurality of sheets of thepaper is fed in order from the paper P on a placing surface 11 a sidetoward the downstream side.

The pair of transporting rollers 16, the reading unit 20 reading thepaper P described above, and a pair of discharging rollers 17 areprovided on the downstream side of the feeding roller 14.

The pair of transporting rollers 16 is provided on an upstream side ofthe reading unit 20 and transports the paper P fed by the feeding roller14 toward the reading unit 20. The pair of transporting rollers 16 isconfigured with a transportation driving roller 16 a and atransportation driven roller 16 b.

The pair of transporting rollers 16 is also provided in a center regionin the medium width direction in the same manner as that of the feedingroller 14 (FIG. 4).

The reading unit 20 includes an upper portion reading sensor 20 aprovided on the upper portion 4 side and a lower portion reading sensor20 b provided on the lower portion 3 side. In the embodiment, the upperportion reading sensor 20 a and the lower portion reading sensor 20 bare constituted by a contact type image sensor module (CISM) as anexample.

After at least one surface of a front surface and a rear surface of thepaper P is read by the reading unit 20, the paper P is nipped by thepair of discharging rollers 17 positioned on the downstream side of thereading unit 20 and is discharged from a discharging port 18 provided ona front surface side of the apparatus of the lower portion 3. The pairof discharging rollers 17 is configured with a discharge driving roller17 a and a discharge driven roller 17 b.

Also, the feeding roller 14, the transportation driving roller 16 a, andthe discharge driving roller 17 a in the embodiment are rotary-driven byat least one driving source (not illustrated) provided inside the lowerportion 3. In addition, the driving source (not illustrated) iscontrolled by the controller 19, and therefore, driving of the feedingroller 14, the transportation driving roller 16 a, and the dischargedriving roller 17 a are controlled. That is, the controller 19 controlsa feeding operation of the paper P.

The paper discharging tray 5 which can be pulled out from thedischarging port 18 toward the front surface side of the apparatus isprovided in the lower portion 3. The paper discharging tray 5 takes astate of being accommodated on a bottom portion of the lower portion 3(FIG. 1) and a state of being pulled to the front surface side of theapparatus which is not illustrated. In a state in which the paperdischarging tray 5 is pulled out, the paper P discharged from thedischarging port 18 can be loaded on the paper discharging tray 5.

Also, as illustrated in FIG. 3, a first detecting portion 22 detectingpresence or absence of the paper P being placed on the medium placingportion 11 is provided on a downstream side of the medium movementdetecting portion 21 in the medium feeding direction and inside aplacing region of the paper by the medium placing portion 11 on theupstream side of the feeding roller 14. In addition, a second detectingportion 23, a third detecting portion 24, and a fourth detecting portion25 are sequentially provided on the downstream side of the feedingroller 14, a downstream side of the pair of transporting rollers 16, anda downstream side of the pair of discharging rollers 17. A position ofthe paper P in the medium feeding direction can be detected by thesecond detecting portion 23 and the third detecting portion 24.

The first detecting portion 22, the second detecting portion 23, thethird detecting portion 24, and the fourth detecting portion 25 areprovided in a center region in the width direction.

As the first detecting portion 22, the second detecting portion 23, thethird detecting portion 24, and the fourth detecting portion 25, a lightsensor including a light emitting portion (illustration is omitted)emitting light and a light receiving portion (illustration is omitted)receiving reflected light of the light emitted from the light emittingportion can be used. In addition, instead of the light sensor, anultrasonic type sensor including a transmitter emitting ultrasonic wavesand a receiver provided to face the transmitter with paper to betransported between the transmitter and the receiver can also be used.In addition, a lever type sensor, which detects displacement of amechanical lever being moved due to a contact of the paper to betransported in an optical type or an electric contact type manner, canalso be used.

Regarding Operation of Feeding Roller

In a case in which an original document (paper P) is set on the mediumplacing portion 11 and is read, the controller 19 controls the drivingof the feeding roller 14 based on detected information of the paper bythe first detecting portion 22, the second detecting portion 23, and thethird detecting portion 24 as illustrated in FIG. 3.

With reference to FIG. 5, a basic operation of the feeding roller 14 ina case in which two or more sheets of the original document (paper P)are set on the medium placing portion 11 and are read will be described.

Also, in FIG. 5, ON of the first detecting portion 22, the seconddetecting portion 23, and the third detecting portion 24 indicates adetected state of the paper, and OFF indicates a non-detected state. Inthe feeding roller 14, ON indicates a driving state, and OFF indicates astop state.

When an original document bundle is set on the medium placing portion11, the first detecting portion 22 detects the paper so as to be an ONstate (the first detecting portion is turned on=the original documentbundle is placed). When the first detecting portion 22 is set to the ONstate, if the original document is started to be read, the feedingroller 14 starts to be driven, and a first sheet of the paper P1 fromthe bottom is fed (the feeding roller starts to feed the paper (P1)).

When the feeding roller 14 feeds the first sheet of the paper P1, thesecond detecting portion 23 on an immediate downstream side of thefeeding roller 14 detects a distal end of the paper P1 (the seconddetecting portion is turned on=a distal end is detected (P1)). When thefeeding roller 14 further feeds the paper P1, and the third detectingportion 24 on an immediate downstream side of the pair of transportingrollers 16 detects the distal end of the paper P1 (the third detectingportion is turned on=the distal end is detected (P1)), the driving ofthe feeding roller 14 is stopped (the feeding roller stops feeding ofthe paper (P1)), and the paper P1 is fed by the pair of transportingrollers 16.

Also, after the driving of the feeding roller 14 is stopped, a rear endside of the paper P1 is still nipped between the feeding roller 14 andthe separating roller 15. In order to suppress nipping of the paper P1between the feeding roller 14 and the separating roller 15 which becomesa transportation load, the feeding roller 14 and the separating roller15 which are stopped to be driven are configured to be idly rotated in atransporting direction of the paper P1.

In addition, a case in which the third detecting portion 24 is turnedoff indicates that a rear end of the first sheet of the paper P1 passesthrough the pair of transporting rollers 16 (the third detecting portionis turned off=the distal end is detected (P1)). At this time, the firstsheet of the paper is fed by the pair of discharging rollers 17.

The feeding roller 14 is stopped until a rear end of the paper P1 passesthrough the feeding roller 14 and is driven again after the rear end ofthe paper P1 passes, and a second sheet of paper P2 is started to befed. That is, when the second detecting portion 23 detects the rear endof the paper P1 (the second detecting portion is turned off=the rear endis detected (P1)), the feeding roller 14 starts to feed a second sheetof the paper P2 (the feeding roller starts to feed (P2)).

Also, a distal end of the paper P2 is detected by the second detectingportion 23 (the second detecting portion is turned on=the distal end isdetected (P2)). When the feeding roller 14 further feeds the paper P2,and the third detecting portion 24 on the immediate downstream side ofthe pair of transporting rollers 16 detects the distal end of the paperP2 (the third detecting portion is turned on=the distal end is detected(P2)), the driving of the feeding roller 14 is stopped (the feedingroller stops feeding (P2)), and the pair of transporting rollers 16feeds the paper P2.

Here, before the second detecting portion 23 detects a rear end of thesecond sheet of the paper (the second detecting portion is turnedoff=the rear end is detected (P2)), in a case in which the firstdetecting portion 22 does not detect the paper (the first detectingportion is turned off), a final original document (second sheet in theinvention) is finished to be fed.

Therefore, in a case in which the second detecting portion 23 detectsthe rear end of the second sheet of the paper after the first detectingportion 22 is turned off (the second detecting portion is turned off=therear end is detected (P2)), the feeding roller 14 is not re-driven.

When the pair of transporting rollers 16 feeds the paper P2, the thirddetecting portion 24 is turned off, and the rear end of the paper P2 isdetected (the third detecting portion is turned off=the rear end isdetected (P2)). The paper P2 is fed by the pair of discharging rollers17, and reading of the paper P2 is completed.

Regarding Medium Movement Detecting Portion

Continuously, with reference to FIGS. 3 and 4, the medium movementdetecting portion 21 will be described.

In the embodiment, as illustrated in FIGS. 3 and 4, the medium movementdetecting portion 21 is positioned distant from the upstream side of thefeeding roller 14 in the medium feeding direction, and is providedinside a placing region of the paper by the medium placing portion 11.

The feeding roller 14 is provided in the center region in the widthdirection, and one medium movement detecting portion 21 is provided inthe center region in the width direction.

In the embodiment, the medium placing portion 11 of the medium feedingdevice 10 is capable of placing a plurality of types of paper havingdifferent sizes thereon. The medium movement detecting portion 21 isprovided inside a placing region where paper having the minimum size(card size such as business card as an example) which can be fed by themedium feeding device 10.

The medium movement detecting portion 21 is configured to be detectablemovement of the paper P being fed by the feeding roller 14 toward boththe medium feeding direction (Y axis direction) and the width direction(X axis direction) intersecting the medium feeding direction.

Such a medium movement detecting portion 21 is, for example, a sensorbased on a principle the same as or similar to that of a sensor which iscapable of detecting two-dimensional (plane) movement being used in amouse for a computer, and known sensors in various methods such as anoptical type (red LED), a laser type, a ball type, a blue LED type, andan infrared ray type (IR) can be used. In the embodiment, the opticaltype (red LED) sensor is used.

However, a user may erroneously place an original document bundle boundby a stapler on the medium placing portion 11 of the medium feedingdevice 10. In a case in which only one corner of the original documentbundle is bound, when a first sheet of the original document bundle isfed, a binding portion is pulled, and therefore, there is a concern thatdamage may be generated in a first sheet of the original document orsheets subsequent to a second sheet of the original document.

In the embodiment, such a transportation failure of the paper can beearly detected by the medium movement detecting portion 21. Hereinafter,based on detected information of the medium movement detecting portion21, a control of feeding of the paper P by the controller 19 will bedescribed.

Regarding Control of Controller

The controller 19 in the medium feeding device 10 is capable ofperforming a “control 1” and a “control 2” for controlling feeding ofthe paper P based on the detected information of the medium movementdetecting portion 21.

That is, the controller 19 receives the detected information by themedium movement detecting portion 21 and stops a job in a case in whicha physical quantity relating to movement of the paper P in the widthdirection (X axis direction) exceeds a third threshold T3 as apredetermined threshold (control 1).

In addition, the controller 19 receives the detected information by themedium movement detecting portion 21 and stops the job, in a case inwhich a stop section, when a moving section, the stop section, and amoving section of the paper P in the medium movement detecting portion21 in the medium feeding direction (Y axis direction) are sequentiallydetected, is shorter than a predetermined a first threshold R1 (control2).

Hereinafter, the “control 1” and the “control 2” will be specificallydescribed in sequence.

Regarding Control 1

The “control 1” is a control in which a transportation failure of thepaper is detected based on the movement of the paper P in the widthdirection (X axis direction) detected by the medium movement detectingportion 21 and transportation of the paper is stopped the scanner 1.

First, detection by the medium movement detecting portion 21 in a casein which the paper is normally fed will be described with reference toFIGS. 5 and 6. In FIG. 6, the paper P before being fed which is set onthe medium placing portion 11 is illustrated by a solid line, and thepaper P which is fed by a predetermined feeding amount y1 by the feedingroller 14 is illustrated by a dotted line. When a position to bedetected by the medium movement detecting portion 21 is set to aposition A in the paper P before being fed (solid line), after the paperis fed by only the feeding amount y1, the position A is straightly movedto a position A1 in the +Y direction, but the position A is not moved inthe X axis direction. That is, the paper P is not moved in the widthdirection (X axis direction). A distance from the position A to theposition A1 is the feeding amount y1.

Here, based on a moving distance and a time being detected by the mediummovement detecting portion 21, a speed of the paper P is obtained as thephysical quantity relating to the movement of the paper. When a movingspeed of the paper P in the Y axis direction is set to Vy, and a movingspeed of the paper P in the X axis direction is set to Vx, changes ofthe moving speed Vy and the moving speed Vx in a case in which aplurality of sheets (two sheets) of the paper is fed by the feedingroller 14 so as to be fed toward the downstream side are illustrated inFIG. 5. In FIG. 5, the first sheet of the paper is set to P1, and thesecond sheet of the paper is set to P2.

As described above, since the paper is not moved in the width direction(X axis direction) at the time of being fed, the moving speed Vx is zero(0). Meanwhile, regarding movement in the Y axis direction, if thefeeding roller 14 starts to feed the paper (the feeding roller starts tofeed the paper (P1)), the first sheet of the paper from the bottom isstarted to be moved, and a predetermined speed is detected as the movingspeed Vy. Also, in FIG. 5, a “moving section (P1)” is a section wherethe movement of the paper P1 is detected by the medium movementdetecting portion 21.

When the first sheet of the rear end of the paper P1 is fed to thedownstream side nearer than the medium movement detecting portion 21,the medium movement detecting portion 21 detects the second sheet of thepaper (which is not fed so as to be stopped), and thus the moving speedVy is zero (0). A section where the moving speed Vy being detected bythe medium movement detecting portion 21 is zero is referred to as a“stop section”.

When a rear end of the first sheet of the paper is detected by thesecond detecting portion (the second detecting portion is turned off=therear end is detected (P1)), the feeding roller 14 starts to feed thesecond sheet of the paper P2 (the feeding roller starts to feed (P2)).Then, the medium movement detecting portion 21 detects a predeterminedmoving speed Vy again. When the rear end of the second sheet of thepaper (final original document) is fed to the downstream side nearerthan the medium movement detecting portion 21, the medium movementdetecting portion 21 becomes a state in which the movement of the paperis not detected. A section where the medium movement detecting portion21 detects the movement of the second sheet of the paper P2 is referredto as a “moving section (P2)”.

Next, for example, as illustrated in FIG. 7, a state in which theoriginal document bundle clipped by a stapler is placed on the mediumplacing portion 11 with a clipped part H thereof toward the downstreamside is considered. In FIG. 7, the first sheet of the paper from thebottom is set to the paper P1 (illustrated by dotted line), and a nextsheet (second sheet of paper) disposed on the first sheet is set to thepaper P2 (illustrated by solid line). In the embodiment, a case in whichtwo sheets of the paper are stapled is described, but a case in whichthree sheets or more of the paper are clipped by a stapler is also thesame.

When the original document bundle is set in a state of FIG. 7, and thefeeding roller 14 starts to feed the original document bundle, asillustrated in FIG. 8, since a clipped part H side (+X direction side)in the paper P1 is not moved so as to remain, and an opposite side (−Xdirection side) distant from the clipped part H side is fed by thefeeding roller 14, the paper is rotary-moved in a clockwise directionbased on a vicinity of the clipped part H in a case in which FIG. 8 isseen in a plan view.

That is, the paper P1 is moved so that the position A detected by themedium movement detecting portion 21 before being fed is moved to aposition A2. The position A2 at this time is a position which is movedin not only the Y axis direction but also the X axis direction withrespect to the position A. Also, the position A2 is moved by only adistance y2 in the +Y direction and a distance x2 in the −X directionfrom the position A.

When the paper P1 is moved from the state of FIG. 7 to a state of FIG.8, the moving speed of the paper P1 obtained from paper detectedinformation of the medium movement detecting portion 21 is illustratedin FIG. 9. In the normal feeding state illustrated in FIG. 5, withrespect to that the moving speed Vx of the paper P in the X axisdirection is zero, in FIG. 9, the paper P1 is moved while being rotatedas illustrated in FIG. 8, and thus the moving speed Vx in the X axisdirection also increases in accordance with an increase of the movingspeed Vy in the Y axis direction.

Here, the controller 19 stops the job in a case in which the movingspeed Vx as the physical quantity relating to the movement of the paperP1 in the width direction (X axis direction) obtained based on thedetected information by the medium movement detecting portion 21 exceedsa third threshold T3 (FIG. 9) as a predetermined threshold. That is, inFIG. 9, at a timing illustrated by a reference number F, rollers(feeding roller 14, a pair of transporting rollers 16, and a pair ofdischarging rollers 17) relating to transportation of the paper arestopped to be driven. Thus, it is possible to early detect the movementof the paper P1 in the width direction lead to a transportation failureof the paper and to suppress damage to be generated in the paper P1.

Also, in a case in which a timing when the moving speed Vx exceeds thethird threshold T3 is in the middle of the driving of the feeding roller14 as illustrated in FIG. 9, at least the driving of the feeding roller14 is stopped, and thereby making it possible to stop the transportationof the paper P1. The timing when the moving speed Vx exceeds the thirdthreshold T3 is later than the feeding of the feeding roller 14 isstopped (P1) in FIG. 9, and in a case in which the paper P1 istransported by the pair of transporting rollers 16, driving of the pairof transporting rollers 16 is stopped, and thereby making it possible tostop the transportation of the paper P1.

In the embodiment, the “third threshold T3” is a moving speed of thepaper in the width direction in order to determine whether or not thepaper passes obliquely, and a specific value thereof is appropriatelyset by a person skilled in the art in accordance with a configuration, asize, and the like of the apparatus.

In addition, as “the physical quantity relating to the movement of thepaper” for setting the “third threshold T3”, in addition to the movingspeed Vx of the paper in the width direction, for example, a movingdistance or an acceleration rate in the width direction can be used.

Regarding Control 2

The “control 2” is a control in which a transportation failure of thepaper is detected based on the movement of the paper P in the mediumfeeding direction (Y axis direction) detected by the medium movementdetecting portion 21, and the transportation of the paper is stopped inthe scanner 1.

For example, as illustrated in FIGS. 10 and 11, a case in which theoriginal document bundle clipped by a stapler is placed on the mediumplacing portion 11 in a state in which the clipped part H thereof ispositioned on the upstream side (rear end side) is considered. The firstsheet of the paper from the bottom is set to the paper P1 (illustratedby dotted line), and a next sheet of the paper (second sheet of paper)is set to the paper P2 (illustrated by solid lie).

As illustrated in FIGS. 10 and 11, in a case in which the paper isplaced on the medium placing portion 11 so that the clipped part H ofthe original document bundle is positioned on the upstream side (rearend side), as illustrated in FIG. 15, the first sheet of the paper fromthe bottom P is fed in a normal state. That is, after the feeding roller14 starts to feed the paper P1 (the feeding roller starts to feed (P1)),and the distal end of the paper P1 is detected by the second detectingportion 23 (the second detecting portion detects the distal end (P1)),if the distal end of the paper P1 detected by the third detectingportion 24 (the third detecting portion detects the distal end (P1)),the feeding roller 14 stops to feed the paper P1 (the feeding rollerstops feeding (P1)).

A section where the movement of the paper P1 is detected by the mediummovement detecting portion 21 is set to the “moving section (P1)” of thepaper P1 in the medium feeding direction (Y axis direction) by themedium movement detecting portion 21.

The “moving section (P1)” in FIG. 16 is substantially the same as the“moving section (P1)” in FIG. 5 which illustrates a normal feeding stateof the paper.

Also, the section may be a temporal section (time when the mediummovement detecting portion 21 detects the movement of the paper), or maybe a distance section where the paper is fed (a distance where the paperis moved while the medium movement detecting portion 21 detects themovement of the paper). In the embodiment, the distance section is usedas the section.

If the paper P1 is continuously transported, the second sheet of thepaper P2 (all sheets subsequent to the second sheet of the paper in acase in which three or more sheets of the original document bundle arestapled) may be reversed and moved along the paper P1 as illustrated inFIG. 12.

If the paper P1 is further fed in a state of FIG. 12, as illustrated inFIGS. 13 and 16, the paper P2 is completely reversed. At this time,since the clipped part H is close to one side of the paper in the widthdirection, the paper P2 is inclined as illustrated in FIG. 16 and is fedalong with the paper P1. Also, after the rear end of the paper P1 passesthrough the medium movement detecting portion 21 as illustrated in FIGS.13 and 16, as illustrated in FIGS. 14 and 17, before the distal end ofthe paper P2 approaches the medium movement detecting portion 21, themedium movement detecting portion 21 is in a state of not detecting themovement of the paper. A section where the medium movement detectingportion 21 does not detect the movement of the paper (sectionillustrated by reference number R in FIG. 15) is set to a “stopsection”.

Also, the “stop” of the paper means a case in which the paperapproaching a detecting region of the medium movement detecting portion21 is stopped, and also means a case in which movement of the paper isnot detected because there is no paper.

Continuously, when the distal end of the paper P2 approaches the mediummovement detecting portion 21, the medium movement detecting portion 21detects movement of the paper P2. A section where the movement of thepaper P2 is detected by the medium movement detecting portion 21 isreferred to as the “moving section (P2)” of the paper P2 in the mediummovement detecting portion 21 in the medium feeding direction (Y axisdirection).

Here, even in a case in which the paper is normally fed (FIG. 5) asdescribed above, the “moving section (P1)”, the “stop section”, and the“moving section (P2)” are detected by the medium movement detectingportion 21. In FIG. 5, a timing of moving from the “stop section” to the“moving section (P2)” is a timing when the rear end of the paper P1 isdetected by the second detecting portion 23, and the feeding roller 14starts to feed the paper P2. Also, a movement distance of the paper P1in the medium feeding direction (+Y direction) during the “stop section”at the time of normal feeding of the paper is set to a distance R1 (FIG.5).

However, since the original document bundle in a case in which a rearend is clipped by the clipped part H is fed (FIG. 15), and the paper P2is transported along with the paper P1, as illustrated in FIGS. 14 and17, the paper P2 may be detected by the medium movement detectingportion 21 earlier than the rear end of the paper P1 which is detectedby the second detecting portion 23. That is, before the timing when thefeeding roller 14 starts to feed the paper P2 (feeding starts in FIG. 5(P2)), the paper P2 is started to be moved. Therefore, in FIG. 15, amovement distance R of the paper P1 in the medium feeding direction (+Ydirection) between the “stop sections” detected by the medium movementdetecting portion 21 may be shorter than the distance R1 at the time ofnormal feeding (FIG. 5).

In such a case described above, the controller 19 receives the detectedinformation by the medium movement detecting portion 21, and controlsthe jot to be stopped in a case in which the distance R in the “stopsection” when the medium movement detecting portion 21 sequentiallydetects the “moving section (P1)”, the “stop section”, and the “movingsection (P2)” of the paper P in the medium feeding direction (Y axisdirection) is shorter than a predetermined first threshold R1 (distanceR1 in “stop section” at the time of normal feeding in FIG. 5.

That is, in FIG. 15, at a timing of moving from the “stop section” tothe “moving section (P2)”, rollers (feeding roller 14, a pair oftransporting rollers 16, and a pair of discharging rollers 17) relatingto transportation of the paper are stopped to be driven.

Accordingly, in a case in which the distance R of the “stop section” isshorter than the first threshold R1, that is, since the job is stoppedby early detecting the feeding state which is not detected during anormal feeding (FIG. 5) (a state in which the subsequent paper P2 alongwith the paper P1 which is fed in advance is fed unintendedly due to thebinding portion H of the stapled original document bundle as illustratedin FIG. 15), it is possible to suppress generation of damage in thepaper P1 and paper subsequent to the paper P2 to be bound with the paperP1 when a transportation failure occurs.

In addition, for example, a punch hole for filing may be opened in thepaper. As illustrated in FIG. 18, in a case of the paper P1 (illustratedby dotted line in FIG. 18) in which a plurality of punch holes N isprovided in the width direction, when the paper P1 is normally fed, anda punch hole N1 among the plurality of punch holes N at a positionoverlapping the medium movement detecting portion 21 in the mediumfeeding direction passes through the medium movement detecting portion21, the medium movement detecting portion 21 detects the second sheet ofthe paper P2 (in stop because it is not fed) through the punch hole N1.That is, a section where the punch hole N1 passes through the mediummovement detecting portion 21 is detected by the medium movementdetecting portion 21 as the “stop section”.

Therefore, a short “stop section” corresponding to a section where thepunch hole N1 passes through the medium movement detecting portion 21between the “moving sections (P1)” at the time of normally feeding thepaper P1 (FIG. 5) is detected. A distance of the short “stop section” isthe distance R2 (FIG. 19) corresponding to a diameter R2 (FIG. 18) of apunch hole N (N1) in the Y axis direction.

That is, as illustrated in FIG. 19, the “stop section” of the distanceR2 is detected between the “moving section (first half of P1)” which isa section where the medium movement detecting portion 21 detects adownstream side of the paper P1 rather than the punch hole N1 and the“moving section (latter half of P1)” which is a section where the mediummovement detecting portion 21 detects an upstream side of the paper P1rather than the punch hole N1.

In a case in which the punch hole N1 is present in the paper P1 to befed, since the medium movement detecting portion 21 detects the nextpaper P2 on the paper P1 through the punch hole N1 in a partcorresponding to the punch hole N1, apparently, the medium movementdetecting portion 21 detects the “stop section”.

However, generally, since the punch hole N1, which is a hole for filing,is small, the “stop section” detected by the medium movement detectingportion 21 in the part corresponding to the punch hole N1 is asignificantly short section (distance R2) and is shorter than the firstthreshold R1 for detecting feeding (transportation failure) of a stapledmedium bundle. Therefore, when the controller 19 performs controllingwith reference to only the first threshold R1, even a normal feeding ofthe paper P1 having the punch hole N (N1) is set to an abnormal feedingstate which causes a transportation failure to be generated, and thus ajob is stopped.

Therefore, in order to suppress or avoid a concern in which the normalfeeding of the paper having a small hole such as the punch hole N isdetermined as the abnormal feeding, the controller 19 is capable ofreferring a second threshold R2 shorter than the first threshold R1, andin a case in which the “stop section” pinched between the “movingsections” (between “moving section (first half of P1)” and “movingsection (latter half of P1)” in FIG. 19) is equal to or smaller than thesecond threshold R2, the job is continued.

Thus, it is possible to suppress false detection of the normal feedingof the paper having a small hole as the abnormal feeding.

Also, even in a case in which the paper P1 floats due to wrinkles orfolds other than the punch hole N and is not detected by the mediummovement detecting portion 21, or a case in the paper P1 is partiallyformed of a material which is not detected by the medium movementdetecting portion 21, the short “stop section” may be present.

Even in such a case, it is possible to avoid detection as the abnormalfeeding and to set the detection as the normal feeding.

In the medium feeding device 10 of the embodiment, the medium movementdetecting portion 21 is configured to be capable of detecting themovement in both the medium feeding direction (Y axis direction) and thewidth direction (X axis direction), and the controller 19 is capable ofperforming the “control 1” and the “control 2” described above, but forexample, the controller 19 can be configured to perform the “control 1”by including the medium movement detecting portion which detects onlythe movement of the paper P in the width direction. In addition, thecontroller 19 can also be configured to perform the “control 2” byincluding the medium movement detecting portion which detects only themovement of the paper P in the feeding direction.

Second Embodiment

Regarding a second embodiment, another example of the medium feedingdevice will be described with reference to FIGS. 20 and 21. FIG. 20 is aview describing paper feeding in the medium feeding device according tothe second embodiment. FIG. 21 is a view describing another example ofthe paper feeding in the medium feeding device according to the secondembodiment.

In the embodiment, the same number is given to the same configuration asthat of the first embodiment, and description thereof will be omitted.In addition, in addition to FIGS. 20 and 21, the drawings used todescribe the first embodiment are appropriately referred to.

As illustrated in FIGS. 20 and 21, the medium feeding device 30according to the embodiment includes a pair of the medium movementdetecting portions which is provided with a gap therebetween so as to bepositioned on both ends of the feeding roller 14, a first mediummovement detecting portion 31 a, and a second medium movement detectingportion 31 b. The +X direction side is set to the first medium movementdetecting portion 31 a, and the −X direction side is set to the secondmedium movement detecting portion 31 b.

Here, for example, in a case in which the original document bundleclipped by a stapler is placed on the medium placing portion 11 in astate in which the clipped part H is positioned toward the downstreamside (distal end side), as illustrated in FIG. 20, the clipped part Hside (+X direction side) is hardly moved, the paper P1 (illustrated bydotted line in FIG. 20) is fed to an opposite side (−X direction side)distant from the clipped part H side, and thus when FIG. 20 is seen inplain view, the paper is rotary-moved in a counterclockwise directionbased on a vicinity of the clipped part H.

That is, before feeding the paper P1, a detection position B by thefirst medium movement detecting portion 31 a and a detection position Cby the second medium movement detecting portion 31 b are respectivelymoved in detection position B1 and a detection position Cl after feedingthe paper P1.

Therefore, as the above description of the control 1 of the firstembodiment, the first medium movement detecting portion 31 a and thesecond medium movement detecting portion 31 b detect the movement of thepaper P1 which is not detected at the time of the normal feeding of thepaper in the X axis direction.

Also, a movement amount d2 of the paper P1 being detected by the secondmedium movement detecting portion 31 b far from the clipped part H whichis a rotation center of the paper P1 increases more than the movementamount d1 of the paper P1 being detected by the first medium movementdetecting portion 31 a close to the clipped part H.

The controller 19 controls for stopping the job, in a case in which adifference between a physical quantity relating to the movement of thepaper detected by the first medium movement detecting portion 31 a and aphysical quantity relating to the movement of the paper detected by thesecond medium movement detecting portion 31 b exceeds a predeterminedthreshold. As the physical quantity relating to the movement of thepaper, a moving speed, a movement distance, an acceleration rate at thetime of moving, and the like are exemplified.

Accordingly, it is possible to detect a transportation failure of thepaper, particularly, the rotation of the paper, and thus damage to begenerated in the paper can be more reliably suppressed.

Also, the physical quantity to be compared may be any one of a physicalquantity relating to movement of the paper in the width direction, aphysical quantity relating to movement of the paper in the feedingdirection, and a physical quantity relating to movement of the paper inboth the width direction and the feeding direction. In a case in whichthe paper is rotated, each difference between the physical quantitiesrelating to the movement in the feeding direction is significant, andthus it is desirable that at least a difference between the physicalquantities relating to the movement in the feeding direction is used. Inaddition, the detectable rotation of the paper is not limited to a casein which the detectable rotation is generated in the stapled originaldocument bundle.

In addition, without comparing the physical quantities relating to themovement of the paper detected by the first medium movement detectingportion 31 a and the second medium movement detecting portion 31 b, in acase in which the first medium movement detecting portion 31 a and thesecond medium movement detecting portion 31 b detect the movement of thepaper in the width direction, the job can be stopped.

In addition, in a case in which the original document bundle clipped bya stapler is placed on the medium placing portion 11 in a state in whichthe clipped part H is positioned toward the upstream side (rear endside), as illustrated in FIG. 21, a distal end of the subsequent paperP2 (illustrated by solid line) along with the paper P1 (illustrated bydotted line) which is transported in advance may be inclinedly fed.

When the paper P2 along with the paper P1 is fed, as above descriptionof the control 2 of the first embodiment with reference to FIG. 15, thefirst medium movement detecting portion 31 a and the second mediummovement detecting portion 31 b respectively detect the “moving section(P1)”, the “stop section”, and the “moving section (P2)”.

However, when the distal end of the paper P2 is inclined, since thetiming when the first medium movement detecting portion 31 a detects thedistal end of the paper P2 and a timing when the second medium movementdetecting portion 31 b detects the distal end of the paper P2 aredifferent from each other, a difference is also generated between the“stop section” detected by the first medium movement detecting portion31 a and the “stop section” detected by the second medium movementdetecting portion 31 b.

Also, the “stop section” detected by the first medium movement detectingportion 31 a corresponds to the distance e1 from the distal end of thepaper P2 to the first medium movement detecting portion 31 a in FIG. 21which is a drawing illustrating a timing when the rear end of the paperP1 (generally in the normal feeding state) is pulled out from adetecting region by the first medium movement detecting portion 31 a andthe second medium movement detecting portion 31 b, and the “stopsection” detected by the second medium movement detecting portion 31 bcorresponds to the distance e2 from the distal end of the paper P2 tothe second medium movement detecting portion 31 b in FIG. 21.

In such a case described above, the controller 19 controls the jot to bestopped in a case in which a difference between the “stop section”detected by the first medium movement detecting portion 31 a and the“stop section” detected by the second medium movement detecting portion31 b exceeds a predetermined threshold. Accordingly, it is possible tomore reliably detect a transportation failure of the paper.

Also, the difference of the “stop sections” means a difference betweendistances or lengths indicated by time of the “stop sections”, and alsomeans a difference between start or finish timings of the “stopsections” even when the lengths of the “stop sections” are the same aseach other.

In addition, with reference to detected information relating to a largerphysical quantity relating to the movement of the paper than the otherto be detected by one of the first medium movement detecting portion 31a and the second medium movement detecting portion 31 b is used, thecontrol 1 described in the first embodiment can also be performed.

Hitherto, the first embodiment and the second embodiment are described,but the invention is not limited to the embodiments, variousmodifications can be made within a range of the invention described inclaims, and it is needless to say that the modifications are alsoincluded in the range of the invention.

For example, in the first embodiment and the second embodiment, thescanner 1 in a center paper feeding manner is described, but forexample, the configuration of the invention can be applied to a scannerin an offset paper feeding manner having a configuration in which oneedge guide 12 is fixed to the medium placing portion 11 and the otheredge guide 12 is moved to the medium placing portion 11.

In addition, the medium feeding device 10 (first embodiment) and themedium feeding device 30 (second embodiment) can also be provided in,for example a recording apparatus represented by a printer, in additionto the scanner (image reading apparatus).

What is claimed is:
 1. A medium feeding device comprising: a mediumplacing portion over which a medium is placed; a feeding rollerconfigured to cooperate with a separating roller to feed the mediumplaced on the medium placing portion by coming into contact with asurface of the medium facing the medium placing portion and beingrotated; a medium movement detecting portion that is positioned in aplacing region of the medium placing portion over which the medium to befed by the feeding roller can be placed, the medium movement detectingportion being upstream of the feeding roller and the separating rollerand being configured to detect movement of the medium toward oppositesides of a width direction intersecting a medium feeding direction, themedium movement detecting portion detecting movement of the medium at alocation disposed in the placing region and spaced from edge guides thatguide edges of the medium moved in the medium feeding direction, themedium movement detecting portion optically detects movement within atwo-dimensional plane; and a controller configured to stop feeding ofthe medium in a case in which a physical quantity relating to themovement of the medium in the width direction based on a detected resultby the medium movement detecting portion exceeds a predeterminedthreshold.
 2. The medium feeding device according to claim 1, wherein apair of the medium movement detecting portions is provided with a gaptherebetween in the width direction, wherein the pair of medium movementdetecting portions is respectively set as a first medium movementdetecting portion and a second medium movement detecting portion, andwherein the controller stops the feeding of the medium in a case inwhich a difference between a physical quantity relating to movement ofthe medium in the width direction being detected by the first mediummovement detecting portion and a physical quantity relating to movementof the medium in the width direction being detected by the second mediummovement detecting portion exceeds a predetermined threshold.
 3. Themedium feeding device according to claim 1, wherein the feeding rolleris provided in a center region of the medium in the width directionintersecting the medium feeding direction, and wherein one mediummovement detecting portion is provided in the center region in the widthdirection.
 4. A medium feeding device comprising: a medium placingportion on which a medium is placed; a feeding roller configured tocooperate with a separating roller to feed the medium placed on themedium placing portion by coming into contact with a surface of themedium facing the medium placing portion and being rotated; a firstmedium movement detecting portion and a second medium movement detectingportion, as a medium movement detecting portion, that are positioned ina placing region of the medium placing portion, are provided with a gaptherebetween in a width direction intersecting a medium feedingdirection as a pair, the medium movement detecting portion beingupstream of the feeding roller and the separating roller and beingconfigured to detect movement of the medium toward opposite sides of anaxis and being set with the axis toward the medium feeding direction,the first medium movement detecting portion and the second mediummovement detecting portion detecting movement of the medium at locationsdisposed in the placing region and spaced from edge guides that guideedges of the medium moved in the medium feeding direction, the mediummovement detecting portion optically detects movement within atwo-dimensional plane; and a controller configured to stop feeding ofthe medium in a case in which a difference between a physical quantityrelating to movement of the medium in the medium feeding direction beingdetected by the first medium movement detecting portion and a physicalquantity relating to movement of the medium in the medium feedingdirection being detected by the second medium movement detecting portionexceeds a predetermined threshold.
 5. An image reading apparatuscomprising: a reading unit that reads a medium; and the medium feedingdevice according to claim 1 that feeds the medium toward the readingunit.
 6. An image reading apparatus comprising: a reading unit thatreads a medium; and the medium feeding device according to claim 2 thatfeeds the medium toward the reading unit.
 7. An image reading apparatuscomprising: a reading unit that reads a medium; and the medium feedingdevice according to claim 3 that feeds the medium toward the readingunit.
 8. The medium feeding device according to claim 4, wherein themedium movement detecting portion is configured to detect movement ofthe medium being fed by the feeding roller toward opposite sides of thewidth direction.
 9. The medium feeding device according to claim 1,wherein the medium movement detecting portion is configured to detectmovement of the medium being fed by the feeding roller in the mediumfeeding direction.
 10. The medium feeding device according to claim 1,wherein the medium movement detecting portion is steadily fixed in themedium placing portion.
 11. The medium feeding device according to claim4, wherein the medium movement detecting portion is steadily fixed inthe medium placing portion.
 12. The medium feeding device according toclaim 1, wherein the movement detected by the medium movement detectingportion includes movement of the medium toward opposite sides of a widthdirection intersecting a medium feeding direction and in the feedingdirection.
 13. The medium feeding device according to claim 4, whereinthe movement detected by the medium movement detecting portion includesmovement of the medium toward opposite sides of a width directionintersecting a medium feeding direction and in the feeding direction.